Year cubic meters 1961 36.03880615400095 1962 35.106169129867624 1963 34.19278493941859 1964 33.30375072169228 1965 32.44807521100415 1966 31.632424145763224 1967 30.856184446421846 1968 30.11628288332931 1969 29.415264257174126 1970 28.750514706089525 1971 28.124672962787205 1972 27.52487918780027 1973 26.939092006050736 1974 26.364095434439957 1975 25.789424602863495 1976 25.22128525147513 1977 24.644286828348303 1978 24.05196995735778 1979 23.456306460209262 1980 22.85789729837026 1981 22.27192672856822 1982 21.69731734585309 1983 21.11768962339029 1984 20.543818290091576 1985 19.98567307040275 1986 19.446054631784776 1987 18.924584376858572 1988 18.41673332603294 1989 17.93212379126054 1990 17.4780471358462 1991 17.061634403570984 1992 16.669683323692144 1993 16.29136785582791 1994 15.929693469528177 1995 15.584356971041833 1996 15.251994598658632 1997 14.926770458273348 1998 14.610055215635576 1999 14.30453762677736 2000 14.011220269258944 2001 13.726033127973118 2002 13.441987788249818 2003 13.164247872150721 2004 12.899492942861555 2005 12.646172364041318 2006 12.40238239843968 2007 12.162675049020141 2008 11.926800502304358 2009 11.695760885501963 2010 11.46100108429093 2011 11.210755545058301 2012 10.960060050607419 2013 10.7091732314791 2014 10.461090997222747 2015 10.232921869932625 2016 10.021643743993902 2017 9.824207015061472 2018 9.639412240694387 2019 9.46802294075448 2020 9.305343628939225